[1/2] input: Allow filtering of i8042 events

Commit Message

Matthew Garrett Dec. 9, 2009, 6:33 p.m. UTC

None

Patch

diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c
index 1df02d2..2d02fe2 100644
--- a/drivers/input/serio/i8042.c
+++ b/drivers/input/serio/i8042.c
@@ -108,11 +108,10 @@  struct i8042_port {
 	int irq;
 	bool exists;
 	signed char mux;
+	bool (*filter)(unsigned char data, unsigned int flags,
+		       struct serio *port);
 };
 
-#define I8042_KBD_PORT_NO	0
-#define I8042_AUX_PORT_NO	1
-#define I8042_MUX_PORT_NO	2
 #define I8042_NUM_PORTS		(I8042_NUM_MUX_PORTS + 2)
 
 static struct i8042_port i8042_ports[I8042_NUM_PORTS];
@@ -139,6 +138,66 @@  void i8042_unlock_chip(void)
 }
 EXPORT_SYMBOL(i8042_unlock_chip);
 
+int i8042_install_filter(int port, bool (*filter)(unsigned char data,
+						  unsigned int flags,
+						  struct serio *port))
+{
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&i8042_lock, flags);
+	if (port >= I8042_NUM_PORTS) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (!i8042_ports[port].exists) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	if (i8042_ports[port].filter) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	i8042_ports[port].filter = filter;
+out:
+	spin_unlock_irqrestore(&i8042_lock, flags);
+	return ret;
+}
+EXPORT_SYMBOL(i8042_install_filter);
+
+int i8042_remove_filter(int port, bool (*filter)(unsigned char data,
+						 unsigned int flags,
+						 struct serio *port))
+{
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&i8042_lock, flags);
+	if (port >= I8042_NUM_PORTS) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (!i8042_ports[port].exists) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	if (!i8042_ports[port].filter || i8042_ports[port].filter != filter) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	i8042_ports[port].filter = NULL;
+out:
+	spin_unlock_irqrestore(&i8042_lock, flags);
+	return ret;
+}
+EXPORT_SYMBOL(i8042_remove_filter);
+
 /*
  * The i8042_wait_read() and i8042_wait_write functions wait for the i8042 to
  * be ready for reading values from it / writing values to it.
@@ -454,8 +513,12 @@  static irqreturn_t i8042_interrupt(int irq, void *dev_id)
 			goto out;
 		}
 
-	if (likely(port->exists))
-		serio_interrupt(port->serio, data, dfl);
+	if (likely(port->exists)) {
+		if (port->filter && port->filter(data, dfl, port->serio))
+			goto out;
+		else
+			serio_interrupt(port->serio, data, dfl);
+	}
 
  out:
 	return IRQ_RETVAL(ret);
diff --git a/include/linux/i8042.h b/include/linux/i8042.h
index 60c3360..02f823b 100644
--- a/include/linux/i8042.h
+++ b/include/linux/i8042.h
@@ -33,12 +33,22 @@ 
 
 struct serio;
 
+#define I8042_KBD_PORT_NO       0
+#define I8042_AUX_PORT_NO       1
+#define I8042_MUX_PORT_NO       2
+
 #if defined(CONFIG_SERIO_I8042) || defined(CONFIG_SERIO_I8042_MODULE)
 
 void i8042_lock_chip(void);
 void i8042_unlock_chip(void);
 int i8042_command(unsigned char *param, int command);
 bool i8042_check_port_owner(const struct serio *);
+int i8042_install_filter(int port, bool (*filter)(unsigned char data,
+						  unsigned int flags,
+						  struct serio *port));
+int i8042_remove_filter(int port, bool (*filter)(unsigned char data,
+						 unsigned int flags,
+						 struct serio *port));
 
 #else
 
@@ -60,6 +70,20 @@  bool i8042_check_port_owner(const struct serio *serio)
 	return false;
 }
 
+int i8042_install_filter(int port, bool (*filter)(unsigned char data,
+                                                  unsigned int flags,
+						  struct serio *port))
+{
+	return -ENODEV;
+}
+
+int i8042_remove_filter(int port, bool (*filter)(unsigned char data,
+						 unsigned int flags,
+						 struct serio *port))
+{
+	return -ENODEV;
+}
+
 #endif
 
 #endif